There has been known a continuously variable transmission for vehicle, which transmits a power via a power transmitting member pressed by a hydraulic actuator to perform a continuous speed change by controlling supply/discharge of an operation oil to/from the hydraulic actuator. A belt-type continuously variable transmission including a pair of variable pulleys, a transmission member, and a pair of hydraulic cylinders can be illustrated as one example of such the continuously variable transmission. In detail, each of an input side variable pulley and an outputs side variable pulley has a construction such that an effective radius thereof can be varied, the transmission member wound around the input side variable pulley and the outputs side variable pulley transmits the power, and each of an input side hydraulic cylinder and an output side hydraulic cylinder varies width of a V-shaped grooves of the input side variable pulley and the outputs side variable pulley.
By the way, in the vehicle provided with the above continuously variable transmission, there has been proposed a controlling system, in which a target drive force is calculated from an output requirement amount and a vehicle speed, a target output of a drive source for achieving the target drive force is calculated, and a target output rotation speed preset for the target output is calculated. Then, a speed change ratio of the continuously variable transmission is controlled such that an actual output speed of the power source coincides with the target output rotation speed. Simultaneous with above speed change ratio control, after a target output torque of the power source is calculated based on the above target output and the actual output rotation speed of the power source, the power source is controlled to output this target output torque. For example, a patent document 1 has disclosed such the controlling system for vehicle provided with the continuously variable transmission.    [Patent Document 1] Japanese Patent Application Laid-open No. 2000-289496
By the way, the above controlling system of vehicle provided with the conventional continuously variable transmission controls the output torque of the power source and the speed change ration of the continuously variable transmission such that the power source operates in a driving condition along an optimal mileage curve. Such controls of the output torque of the power source and the speed change ration of the continuously variable transmission making a point of the mileage may suppress the target drive force and the output rotation speed of the drive source against an acceleration requirement by a driver. Thus, there has been a problem that sufficient accelerating feeling responsive to the driver's acceleration requirement can not be obtained from the vehicle.
The present invention is made in view of the above circumstances and has an object to provide a controlling system for vehicle provided with a continuously variable transmission in which a sufficient accelerating feeling can be rendered from the vehicle in response to the driver's acceleration requirement.